U.S. Pat. No. 4,759,646 discloses a small, ink jet printer wherein print media is advanced line-by-line through a print zone by a rotary platen and a print head carriage traverses the print zone to print on successively advanced lines. This printer is designed for easy portability and achieves enhanced compactness by incorporating battery power sources within the platen.
U.S. patent application Ser. No. 185,340, filed Apr. 12, 1988, describes a portable printer construction for handling three different types of print media, viz: sheet print media, continuous print media with tractor-feed perforation edges and continuous print media without edge perforations. The continuous print media can be provided in either roll or fanfold formats. The tractor-feed continuous media usually is in the fanfold format and has the advantage of providing controlled feeding, without skew. The roll format media can be utilized without edge perforations and is compact and convenient to carry in a briefcase.
The printer described in the Ser. No. 185,340 application has a lid construction that fully opens to prevent re-feed in the fanfold print mode. In the roll media print mode, the lid is closed and has a guide slot, which contacts media edges, to prevent media skewing. This printer configuration is highly useful, but presents one difficulty. Thus, in the mode using non-perforated, continuous print media, the lid (and its guide slot) are required in the closed condition to prevent skew. Therefore the lid cannot protect against re-feeding the lead end into the media ingress in the rear of the printer, as it does in the fully open condition.